Kai,
It is not uncommon for illicit dumpers to pull into a dark corner of a parking lot and dump in a convenient storm drain. I think that is what they were suggesting as a potential source. However, it could easily have been from a source at U of M and no one is owning up to it. Our resources for conducting a criminal investigation for an event like this are limited and are very unlikely to yield any solid results. From our perspective, it is unfortunate, but incidents this like this happen and it is unlikely we’ll ever figure it out. We try hard to investigate and respond to complaints and, in this case, get U of M to perform appropriately, but circumstances are such that it does not always work out. Realistically, the best we can hope for is to push U of M to do better next time (and they are generally very responsive and take their obligations seriously). They are no obligations for U of M to make public notice for an incident like this. Obviously, there are spills where it is necessary to contact the County Health Dept and other agencies to evaluate risks and determine what notice/posting/warnings may be necessary. The pipeline spill on the West side of the state (which we have staff engaged on currently) is on the far side of the spectrum and there have obviously been many warnings about contact with the river and prohibitions against using the water for irrigation etc., but, as I said, that is the extreme example. It is not easy to convey or to accept sometimes, but we have to prioritize our efforts and beyond interfacing with U of M on getting reports submitted and improving practices there is not much more we can effectively do in this case.
-Jon
Jon E. Russell, Supervisor
Water Resources Division
MI Department of Natural Resources & Environment
Jackson District Office